BioChem - DOS

Automated UV-C mutagenesis of Kluyveromyces marxianus NRRL Y-1109 and selection for microaerophilic growth and ethanol production at elevated temperature on biomass sugars

Journal of laboratory automation

Hughes, Stephen R.; Bang, Sookie S.; Cox, Elby J.; Schoepke, Andrew; Ochwat, Kate; Pinkelman, Rebecca; Nelson, Danielle; Qureshi, Nasib; Gibbons, William R.; Kurtzman, Cletus P.; Bischoff, Kenneth M.; Liu, Siqing; Cote, Gregory L.; Rich, Joseph O.; Jones, Marjorie A.; Cedeñ o, David; Doran-Peterson, Joy; Riañ o-Herrera, Nestor M.; Rodrí guez-Valencia, Nelson; Ló pez-Nú ñ ez, Juan C.

<P>The yeast <I>Kluyveromyces marxianus</I> is a potential microbial catalyst for fuel ethanol production from a wide range of biomass substrates. To improve its growth and ethanol yield at elevated temperature under microaerophilic conditions, <I>K. marxianus</I> NRRL Y-1109 was irradiated with UV-C using automated protocols on a robotic platform for picking and spreading irradiated cultures and for processing the resulting plates. The plates were incubated under anaerobic conditions on xylose or glucose for 5 mo at 46 &#x00B0;C. Two <I>K. marxianus</I> mutant strains (designated 7-1 and 8-1) survived and were isolated from the glucose plates. Both mutant strains, but not wild type, grew aerobically on glucose at 47 &#x00B0;C. All strains grew anaerobically at 46 &#x00B0;C on glucose, galactose, galacturonic acid, and pectin; however, only 7-1 grew anaerobically on xylose at 46 &#x00B0;C. <I>Saccharomyces cerevisiae</I> NRRL Y-2403 did not grow at 46 &#x00B0;C on any of these substrates. With glucose as a carbon source, ethanol yield after 3 d at 46 &#x00B0;C was higher for 8-1 than for wild type (0.51 and 0.43 g ethanol/g glucose, respectively). With galacturonic acid as a carbon source, the ethanol yield after 7 d at 46 &#x00B0;C was higher for 7-1 than for wild type (0.48 and 0.34 g ethanol/g galacturonic acid, respectively). These mutant strains have potential application in fuel ethanol production at elevated temperature from sugar constituents of starch, sucrose, pectin, and cellulosic biomass.</P>

2013

SAGE Publications

cc-by-nc-nd

2211-0682

2211-0690

18

4

pp.276-290

10.1177/2211068213480037

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART66636740

http://slas-technology.org/article/S2472630322016272/pdf

thermotolerant ethanologenic yeast; yeast UV-C mutagenesis; Kluyveromyces marxianus yeast; biomass sugars